Water damaged Samsung Galaxy J6, hard-reset freezes at logo

After dropping my Galaxy J6 in water (I got it out almost immediately), I attempted to turn it off, but the touch screen won’t function - the touch screen is needed to turn it off. So I tried doing a hard reset by holding all three power and volume buttons down at once, thinking this would fix the touch screen, at which point I could power it off. But even as I write this 20 minutes later, all that appears when I hard reset is the Samsung Galaxy J6 logo - nothing happens.

So what do I do? Is there any way to straight-up turn it off at this point? Can it still be put in rice or vacuumed or whatever even when it’s technically still powered on?

First do not turn on your phone and then you need to remove the battery as soon as possible from the phoneto minimize further damage.

Then you need to dis-assemble the rest of the phone and clean all the affected parts using Isopropyl Alcohol 99%+ (available from electronics parts stores), to remove all traces of corrosion and water. Do not use "rubbing alcohol" as in some cases this is only 70% IPA or less, can contain scents and is not as effective. If you do check the label to verify the amount of IPA

As always with electronics, especially surface mounted PCBs be gentle when handling and especially when brushing away the corrosion. You do not want to remove any components from the board.

Hopefully after you have done all this the phone might possibly work correctly again.

Here is a link to a video that shows how to disassemble the phone which may be of some help.

If this process seems too daunting, take your phone to a reputable, professional phone repair service, experienced in water damage repair and ask for a quote for a repair. If you decide to do this, do it sooner than later.